r5s77631ay266bgv Renesas Electronics Corporation., r5s77631ay266bgv Datasheet - Page 257

• Manufacturer Part Number: r5s77631ay266bgv
• Description: Renesas 32-bit Risc Microcomputer Superhtm Risc Engine Family Sh-4a Series
• Manufacturer: Renesas Electronics Corporation.

7.2.1
CCR controls the cache operating mode, the cache write mode, and invalidation of all cache
entries.
CCR modifications must only be made by a program in the non-cacheable P2 area. After CCR has
been updated, execute one of the following three methods before an access (including an
instruction fetch) to the cacheable area is performed.
1. Execute a branch using the RTE instruction. In this case, the branch destination may be the
2. Execute the ICBI instruction for any address (including non-cacheable area).
3. If the R2 bit in IRMCR is 0 (initial value) before updating CCR, the specific instruction does
Note that the method 3 may not be guaranteed in the future SuperH Series. Therefore, it is
recommended that the method 1 or 2 should be used for being compatible with the future SuperH
Series.
Initial value:
Initial value:
Bit
31 to 12
11
cacheable area.
not need to be executed. However, note that the CPU processing performance will be lowered
because the instruction fetch is performed again for the next instruction after CCR has been
updated.
R/W:
R/W:
Bit:
Bit:
Cache Control Register (CCR)
Bit Name

ICI
31
15
R
R
0
0
30
14
R
R
0
0
29
13
R
R
0
0
Initial
Value
All 0
0
28
12
R
R
0
0
R/W
ICI
27
11
R
0
0
R/W
R
R/W
26
10
R
R
0
0
Description
Reserved
For details on reading from or writing to these bits, see
description in General Precautions on Handling of
Product.
IC Invalidation Bit
When 1 is written to this bit, the V bits of all IC entries
are cleared to 0. This bit is always read as 0.
25
R
R
0
9
0
R/W
ICE
24
R
0
8
0
23
R
R
0
7
0
Rev. 1.00 Oct. 01, 2007 Page 191 of 1956
22
R
R
0
6
0
21
R
R
0
5
0
20
R
R
0
4
0
R/W
OCI
19
R
0
3
0
Section 7 Caches
REJ09B0256-0100
R/W
CB
18
R
2
0
0
R/W
WT
17
R
0
1
0
OCE
R/W
16
R
0
0
0